Fast-food workers and labor groups will hold another round or protests around the country Tuesday, including in Philadelphia.

The protests are planned for about 30 cities, but it's not clear what the scope of the turnout will be.

It's part of an ongoing push by labor groups to build support for pay of $15 an hour and the right to unionize.

Organizers have also been referring workers to attorneys, who filed lawsuits in three states last week saying McDonald's was stealing their wages.

McDonald's Corp. said it planned to investigate the allegations and take necessary actions. A representative for the company, based in Oak Brook, Ill., did not immediately provide comment on the planned protests.

Last summer, similar walkouts and protests reached about 60 cities, including New York, Chicago and Detroit.

But the turnout varied significantly, with some targeted restaurants seemingly operating normally and others temporarily unable to do business because they had too few employees.